Various basic input/output systems (BIOSs) may be used in different applications. Even for the same application, there are various BIOS versions in response to the different requirements for different clients. Since there may be several BIOS versions available at the same time for a BIOS supplier, it is important to ensure the BIOS of a sub-system for use with a specified system to be consistent with the BIOS of the specified system. For example, when a video graphics array (VGA) chip is used with a computer system, the VGA BIOS should be consistent with the BIOS of the computer system. Sometimes, a wrong package including specified system and sub-system with inconsistent BIOS versions might be packed together and delivered to the client. Unfortunately, the client would not be conscious of the mistake until the BIOS of the sub-system is executed in the specified system and some specific functions of the sub-system cannot be executed normally. If the wrong package is sold to the end user, a lot of troubles might be rendered.